Many advances in understanding the pathogenesis of autoimmune disease have been gained by studying animal models of systemic lupus erythematosus (SLE). In the past 19 years, hundreds of scientific papers have described investigations of immunologic, genetic, and virologic aspects of disease in New Zealand mice, which are widely recognized as animal models of SLE. Recently, spontaneous autoimmune disease analogous to SLE was described by the applicant in another strain, the Palmerston North (PN) mouse. Inbred PN mice produce ANA, LE cells, and anti-DNA; immunoglobulins and complement are deposited along glomerular basement membranes at an early age. Outbred Swan mice, another strain with autoimmune disease, were acquired by the Principal Investigator in 1977. The project described in this application is designed to establish pathogen-free foundation stocks of inbred autoimmune PN and Swan mice for distribution to other investigators. Both strains of mice will be cesarean-derived and raised on pathogen-free foster mothers in a lamimar flow hood. Mice will be monitored periodically for viral, bacterial, and parasitic infections. Swan mice will be inbred, and presence of autoimmune disease in the inbred mice will be documented by testing for anti-DNA, direct Coombs tests, ANA, and renal deposits of immunoglobulins and complement. Inbreeding will be documented by reciprocal skin grafting and H-2 typing. Establishment of the colonies described in this application will conserve a valuable resource and answer a growing demand for high-quality animal models of autoimmune disease.